To be comparable with the [1]} model, the serpentinization algorithm itself is tested in a selected layer of a sphere, with the homogeneous and isotropic distribution of the components within that layer. Due to the simple forward Euler scheme, the model remains sensitive to the choice of the time step. We explore this in Sect. REF  to find the optimal (largest allowable) time step for our calculations.
Apart from the improvements discussed below, this is the same scheme as was used in [1]} (see the model scheme in Fig REF .).
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